High P levels in surface waters can cause algae blooms and increase water treatment costs in reservoirs used for potable water. Sediments can buffer soluble P concentrations in ditches and streams that feed into these reservoirs. Our study area included ditches and streams that serve as the headwaters of the Eagle Creek reservoir, one of the primary sources of potable water for Indianapolis IN. Our objectives were to 1) relate surface water P concentrations to sediment P and 2) determine if differences in land use are related to ditch and stream water P concentrations and sediment P status. We will present relationships between water and sediment P concentrations in subwatersheds dominated by residential homes, row-crop agriculture, and livestock agriculture. Temporal changes in P exchange characteristics of bed sediments also will be discussed in this poster.